## Copyright (C) 2000-2011 Teemu Ikonen
##
## This file is part of Octave.
##
## Octave is free software; you can redistribute it and/or modify it
## under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 3 of the License, or (at
## your option) any later version.
##
## Octave is distributed in the hope that it will be useful, but
## WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
## General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with Octave; see the file COPYING.  If not, see
## <http://www.gnu.org/licenses/>.

## -*- texinfo -*-
## @deftypefn {Function File} {@var{h} =} __errplot__ (@var{fstr}, @var{p}, @dots{})
## Undocumented internal function.
## @end deftypefn

## Created: 18.7.2000
## Author: Teemu Ikonen <tpikonen@pcu.helsinki.fi>
## Keywords: errorbar, plotting

function h = __errplot__ (fstr, p, varargin)

  if (nargin < 4 || nargin > 8) # at least two data arguments needed
    print_usage ();
  endif

  [fmt, key] = __pltopt__ ("__errplot__", fstr);

  [len, nplots] = size (varargin{1});
  h = [];

  for i = 1:nplots
    ## Set the plot type based on linestyle.

    if (strcmp (fmt.errorstyle, "~"))
      ifmt = "yerr";
    elseif (strcmp (fmt.errorstyle, ">"))
      ifmt = "xerr";
    elseif (strcmp (fmt.errorstyle, "~>"))
      ifmt = "xyerr";
    elseif (strcmp (fmt.errorstyle, "#"))
      ifmt = "box";
    elseif (strcmp (fmt.errorstyle, "#~"))
      ifmt = "boxy";
    elseif (strcmp (fmt.errorstyle, "#~>"))
      ifmt = "boxxy";
    else
      ifmt = "yerr";
    endif

    hg = hggroup ("parent", p);
    h = [h; hg];
    args = __add_datasource__ ("__errplot__", hg, 
                               {"x", "y", "l", "u", "xl", "xu"});

    if (isempty (fmt.color))
      fmt.color = __next_line_color__ ();
    endif
    if (isempty (fmt.marker) && isempty (fmt.linestyle))
      [fmt.linestyle, fmt.marker] = __next_line_style__ ();
    endif
    hl = [(__line__ (hg, "linestyle", fmt.linestyle, "marker", fmt.marker,
                   "color", fmt.color)),
          (__line__ (hg, "linestyle", "-", "marker", "none",
                   "color", fmt.color))];

    switch (numel(varargin))
      case 2
        ydata = varargin{1}(:,i);
        xdata = 1:numel(ydata);
        if (strcmp (ifmt, "xerr") || strcmp (ifmt, "box"))
          xldata = varargin{2}(:,i);
          xudata = ldata;
          ldata = [];
          udata = [];
        elseif (strcmp (ifmt, "yerr") || strcmp (ifmt, "boxy"))
          ldata = varargin{2}(:,i);
          udata = ldata;
          xldata = [];
          xudata = [];
        else
          error ("errorbar: 2 column errorplot is only valid or xerr or yerr");
        endif
      case 3
        if (strcmp (ifmt, "boxxy") || strcmp (ifmt, "xyerr"))
          ydata = varargin{1}(:,i);
          xdata = 1:numel(ydata);
          xldata = varargin{2}(:,i);
          xudata = xldata;
          ldata = varargin{3}(:,i);
          udata = ldata;
        elseif (strcmp (ifmt, "xerr") || strcmp (ifmt, "box"))
          xdata = varargin{1}(:,i);
          ydata = varargin{2}(:,i);
          xldata = varargin{3}(:,i);
          xudata = xldata;
          ldata = [];
          udata = [];
        else # yerr or boxy
          xdata = varargin{1}(:,i);
          ydata = varargin{2}(:,i);
          ldata = varargin{3}(:,i);
          udata = ldata;
          xldata = [];
          xudata = [];
        endif
      case 4
        if (strcmp (ifmt, "boxxy") || strcmp (ifmt, "xyerr"))
          xdata = varargin{1}(:,i);
          ydata = varargin{2}(:,i);
          xldata = varargin{3}(:,i);
          xudata = xldata;
          ldata = varargin{4}(:,i);
          udata = ldata;
        elseif (strcmp (ifmt, "xerr") || strcmp (ifmt, "box"))
          xdata = varargin{1}(:,i);
          ydata = varargin{2}(:,i);
          xldata = varargin{3}(:,i);
          xudata = varargin{4}(:,i);
          ldata = [];
          udata = [];
        else # yerr or boxy
          xdata = varargin{1}(:,i);
          ydata = varargin{2}(:,i);
          ldata = varargin{3}(:,i);
          udata = varargin{4}(:,i);
          xldata = [];
          xudata = [];
        endif
      case 6 # boxxy, xyerr
        if (strcmp (ifmt, "boxxy") || strcmp (ifmt, "xyerr"))
          xdata = varargin{1}(:,i);
          ydata = varargin{2}(:,i);
          xldata = varargin{3}(:,i);
          xudata = varargin{4}(:,i);
          ldata = varargin{5}(:,i);
          udata = varargin{6}(:,i);
        else
          error ("errorbar: error plot with 6 columns only valid for boxxy and xyerr");
        endif        
      otherwise
        error ("errorbar: error plot requires 2, 3, 4 or 6 arguments.");
    endswitch

    addproperty ("xdata", hg, "data", xdata(:))
    addproperty ("ydata", hg, "data", ydata(:))
    addproperty ("ldata", hg, "data", ldata(:))
    addproperty ("udata", hg, "data", udata(:))
    addproperty ("xldata", hg, "data", xldata(:))
    addproperty ("xudata", hg, "data", xudata(:))
    addproperty ("format", hg, "string", ifmt);

    addproperty ("color", hg, "linecolor", get (hl(1), "color"))
    addproperty ("linewidth", hg, "linelinewidth", get (hl(1), "linewidth"))
    addproperty ("linestyle", hg, "linelinestyle", get (hl(1), "linestyle"))
    addproperty ("marker", hg, "linemarker", get (hl(1), "marker"))
    addproperty ("markerfacecolor", hg, "linemarkerfacecolor", 
                 get (hl(1), "markerfacecolor"))
    addproperty ("markeredgecolor", hg, "linemarkerfacecolor", 
                 get (hl(1), "markeredgecolor"))
    addproperty ("markersize", hg, "linemarkersize", 
                 get (hl(1), "markersize"))

    fcn = {@update_props, hl};
    addlistener (hg, "color", fcn);
    addlistener (hg, "linewidth", fcn); 
    addlistener (hg, "linestyle", fcn); 
    addlistener (hg, "marker", fcn); 
    addlistener (hg, "markerfacecolor", fcn); 
    addlistener (hg, "markersize", fcn);

    fcn = {@update_data, hl};
    addlistener (hg, "xdata", fcn);
    addlistener (hg, "ydata", fcn);
    addlistener (hg, "ldata", fcn);
    addlistener (hg, "udata", fcn);
    addlistener (hg, "xldata", fcn);
    addlistener (hg, "xudata", fcn);
    addlistener (hg, "format", fcn);

    hax = ancestor (hg, "axes");
    addlistener (hax, "xscale", fcn);
    addlistener (hax, "yscale", fcn);

    update_data (hg, [], hl)

  endfor

endfunction

function [xdata, ydata] = errorbar_data (xdata, ydata, ldata, udata, 
                                         xldata, xudata, ifmt,
                                         xscale, yscale)
  if (strcmp (xscale, "linear"))
    dx = 0.01 * (max (xdata(:)) - min (xdata(:)));
    xlo = xdata - dx;
    xhi = xdata + dx;
  else
    n = xdata > 0;
    rx = exp(0.01 * (max (log(xdata(n))) - min (log(xdata(n)))));
    xlo = xdata/rx;
    xhi = xdata*rx;
  endif
  if (strcmp (yscale, "linear"))
    dy = 0.01 * (max (ydata(:)) - min (ydata(:)));
    ylo = ydata - dy;
    yhi = ydata + dy;
  else
    n = ydata > 0;
    ry = exp(0.01 * (max (log(ydata(n))) - min (log(ydata(n)))));
    ylo = ydata/ry;
    yhi = ydata*ry;
  endif
  nans = NaN + xdata(:);
  if (strcmp (ifmt, "yerr"))
    xdata = [xdata, xdata, nans, ...
             xlo, xhi, nans, ...
             xlo, xhi, nans];
    ydata = [ydata-ldata, ydata+udata, nans, ...
             ydata+udata, ydata+udata, nans, ...
             ydata-ldata, ydata-ldata, nans];
  elseif (strcmp (ifmt, "xerr"))
    xdata = [xdata-xldata, xdata+xudata, nans, ...
             xdata+xudata, xdata+xudata, nans, ...
             xdata-xldata, xdata-xldata, nans];
    ydata = [ydata, ydata, nans, ...
             ylo, yhi, nans, ...
             ylo, yhi, nans];
  elseif (strcmp (ifmt, "boxy"))
    dx = 0.01 * (max (xdata(:)) - min (xdata(:)));
    xdata = [xlo, xhi, xhi, xlo, xlo, nans];
    ydata = [ydata-ldata, ydata-ldata, ydata+udata, ydata+udata, ...
             ydata-ldata, nans];
  elseif (strcmp (ifmt, "box"))
    dy = 0.01 * (max (ydata(:)) - min (ydata(:)));
    xdata = [xdata-xldata, xdata+xudata, xdata+xudata, xdata-xldata, ...
             xdata-xldata, nans];
    ydata = [ylo, ylo, yhi, yhi, ylo, nans];
  elseif (strcmp (ifmt, "boxxy"))
    xdata = [xdata-xldata, xdata+xudata, xdata+xudata, xdata-xldata, ...
             xdata-xldata, nans];
    ydata = [ydata-ldata, ydata-ldata, ydata+udata, ydata+udata, ...
             ydata-ldata, nans];
  elseif (strcmp (ifmt, "xyerr"))
    [x1, y1] = errorbar_data (xdata, ydata, ldata, udata, 
                              xldata, xudata, "xerr", xscale, yscale);
    [x2, y2] = errorbar_data (xdata, ydata, ldata, udata, 
                              xldata, xudata, "yerr", xscale, yscale);
    xdata = [x1; x2];
    ydata = [y1; y2];
    return
  else
      error ("errorbar: valid error bar types are xerr, yerr, boxxy, and xyerr.")
  endif
  xdata = xdata.'(:);
  ydata = ydata.'(:);
endfunction

function update_props (hg, dummy, hl)
  set (hl, "color", get (hg, "color"), 
           "linewidth", get (hg, "linewidth"));,
  set (hl(1), "linestyle", get (hg, "linestyle"), 
              "marker", get (hg, "marker"),
              "markersize", get (hg, "markersize"),
              "markerfacecolor", get (hg, "markerfacecolor"),
              "markeredgecolor", get (hg, "markeredgecolor"));
endfunction

function update_data (hg, dummy, hl)

  if (strcmp (get (hg, "type"), "axes"))
    hax = hg;
    hg = ancestor (hl(1), "hggroup");
  else
    hax = ancestor (hg, "axes");
  endif
  xscale = get (hax, "xscale");
  yscale = get (hax, "yscale");

  xdata = get (hg, "xdata");
  ydata = get (hg, "ydata");
  ldata = get (hg, "ldata");
  udata = get (hg, "udata");
  xldata = get (hg, "xldata");
  xudata = get (hg, "xudata");
  ifmt = get (hg, "format");

  set (hl(1), "xdata", xdata);
  set (hl(1), "ydata", ydata);

  [errorbar_xdata, errorbar_ydata] = ...
          errorbar_data (xdata, ydata, ldata, udata, xldata, xudata, ...
                         ifmt, xscale, yscale);

  set (hl(2), "xdata", errorbar_xdata);
  set (hl(2), "ydata", errorbar_ydata);

endfunction